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Related papers: Finding cool subdwarfs using a V-J reduced proper-…

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We report the discovery of seven high proper motion stars with proper motions between about 0.7 and 2.2 arcsec/yr. They were detected in an archival search using multi-epoch positions in the optical SuperCOSMOS Sky Surveys and in the…

Astrophysics · Physics 2009-11-10 R. -D. Scholz , I. Lehmann , I. Matute , H. Zinnecker

We present revised stellar properties for 172 K2 target stars that were identified as possible hosts of transiting planets during Campaigns 1-17. Using medium-resolution near-infrared spectra acquired with the NASA Infrared Telescope…

Large numbers of low-to-medium resolution spectra of M-type dwarf stars from both the local Galactic disk and halo are available from various surveys. In order to fully exploit these data, we develop a template-fit method using a set of…

Solar and Stellar Astrophysics · Physics 2020-03-11 Neda Hejazi , Sebastien Lepine , Derek Homeier , R. Michael Rich , Michael M. Shara

We present results from an observing campaign to identify low-metallicity stars in the Best & Brightest Survey. From medium-resolution (R ~ 1, 200 - 2, 000) spectroscopy of 857 candidates, we estimate the stellar atmospheric parameters…

Several large stellar spectroscopic surveys are producing overwhelming amounts of data that can be used for determining stellar atmospheric parameters and chemical abundances. Nonetheless, the accuracy achieved in the derived astrophysical…

Solar and Stellar Astrophysics · Physics 2021-06-30 Riano E. Giribaldi , André R. da Silva , Rodolfo Smiljanic , Deysi Cornejo Espinoza

The majority of hot subdwarf stars are low-mass core-helium-burning stars. Their atmospheres are generally helium deficient; however a minority have extremely helium-rich surfaces. An additional fraction have an intermediate surface-helium…

Solar and Stellar Astrophysics · Physics 2017-04-12 P. Martin , C. S. Jeffery , Naslim N. , V. M. Woolf

A photometric and spectroscopic analysis of 152 cool white dwarf stars is presented. The discovery of 7 new DA white dwarfs, 2 new DQ white dwarfs, 1 new magnetic white dwarf, and 3 weak magnetic white dwarf candidates, is reported, as well…

Astrophysics · Physics 2009-10-31 P. Bergeron , S. K. Leggett , Maria Teresa Ruiz

We assembled a catalogue of bright, hot subdwarf and white dwarf stars extracted from a joint ultraviolet, optical, and infrared source list. The selection is secured using colour criteria that correlate well with effective temperatures…

Solar and Stellar Astrophysics · Physics 2015-05-19 S. Vennes , A. Kawka , P. Nemeth

In the search for metal-poor stars, large spectroscopic surveys are an invaluable tool. However, the spectra of metal-poor stars can be difficult to analyse because of the relative lack of available lines, which can also lead to…

With the dual aims of enlarging the list of extremely metal-poor stars identified in the Galaxy, and boosting the numbers of moderately metal-deficient stars in directions that sample the rotational properties of the thick disk, we have…

We present and discuss the results of a search for extremely metal-poor stars based on photometry from data release DR1.1 of the SkyMapper imaging survey of the southern sky. In particular, we outline our photometric selection procedures…

We explore the stellar content of the Javalambre Photometric Local Universe Survey (J-PLUS) Data Release 2 and show its potential to identify low-metallicity stars using the Stellar Parameters Estimation based on Ensemble Methods (SPEEM)…

We present a new sample of M subdwarfs compiled from the 7th data release of the Sloan Digital Sky Survey. With 3517 new subdwarfs, this new sample significantly increases the number of spectroscopically confirmed low-mass subdwarfs. This…

Solar and Stellar Astrophysics · Physics 2015-06-22 Antonia Savcheva , Andrew A. West , John J. Bochanski

Identification of metal-poor stars among field stars is extremely useful for studying the structure and evolution of the Galaxy and of external galaxies. We search for metal-poor stars using the artificial neural network (ANN) and extend…

Solar and Stellar Astrophysics · Physics 2015-06-16 Sunetra Giridhar , Aruna Goswami , Andrea Kunder , S. Muneer , G. Selvakumar

We present new grids of colors and bolometric corrections for F-K stars having 4000 K < Teff < 6500 K, 0.0 < log g < 4.5 and -3.0 < [Fe/H] < 0.0. A companion paper extends these calculations into the M giant regime. Colors are tabulated for…

Astrophysics · Physics 2009-10-12 Mark L. Houdashelt , Roger A. Bell , Allen V. Sweigart

We present results of high resolution (~ 55000) spectral observations of 830 photometrically pre-selected candidate red giants in the magnitude range of V = 9-12. We develop a pipeline for automated determination of the stellar atmospheric…

Solar and Stellar Astrophysics · Physics 2015-05-20 Dmitry Bizyaev , Verne V. Smith , Katia Cunha

We present moderate resolution spectroscopy of 112 cool dwarf stars to supplement the observations we have already presented in the Palomar/MSU Nearby-Star Spectroscopic Survey. The sample consists of 72 suspected nearby stars added to the…

Astrophysics · Physics 2009-10-30 John E. Gizis , I. Neill Reid

The Palomar-Green (PG) survey for UV-excess objects selected objects with U-B<-0.46 for spectroscopic follow-up. The color selection was done from photographic photometry, with typical error sigma_(U-B)=0.38. Spectroscopic detection of the…

Astrophysics · Physics 2007-05-23 R. A. Wade , M. A. Stark , R. F. Green

A metallicity, chemical composition, and kinematic survey has been conducted for a sample of 340 candidate field red horizontal branch stars. High resolution, high signal-to-noise spectra were gathered with the McDonald Observatory 2.7m…

Solar and Stellar Astrophysics · Physics 2018-05-23 Melike Afşar , Zeynep Bozkurt , Gamze Böcek Topcu , Dana~I. Casetti-Dinescu , Christopher Sneden , Gizem Şehitoğlu

We present a catalog of uniformly determined stellar properties and abundances for 1626 F, G, and K stars using an automated spectral synthesis modeling procedure. All stars were observed using the HIRES spectrograph at Keck Observatory.…

Solar and Stellar Astrophysics · Physics 2016-08-24 John M. Brewer , Debra A. Fischer , Jeff A. Valenti , Nikolai Piskunov